X chromosome actually looks like pasta, not the letter X

A 3-D model of the X chromosome shows the chromosome looks less like the letter X and more like a plate of pasta.

This photo shows Human telomeres (the dots on the tips of the x-shaped chromosomes) (green) and centromeres (red) on metaphase chromosomes. The image was made using digital fluorescence microscopy.(Photo: Handout)

Story Highlights

Scientists have built the first of its kind 3-D model of the X chromosome

The chromosome doesn't resemble an X, but looks more like a plate of pasta or a lumpy blob

The designation "X" may have been a placeholder when the chromosome was first discovered

Here's your fun fact for the day: Contrary to popular belief, the X chromosome isn't shaped like an X at all — something that scientists have actually long been aware of. What they haven't known, however, is what that shape is ... until now.

Per a paper published in Nature, the first 3-D model of the chromosome has been made using measurements taken of the X chromosome in mice, and it depicts what LiveScience likens to "amoebas" and "lumpy blobs"; the Christian Science Monitor prefers "a heap of threaded-up vermicelli."

The model, which is tinier than a red blood cell, provides a "map of how the chromosome folds, which parts touch and where, and who is next to whom," explains paper author Peter Fraser.

Before sharing the implications of this, the Monitor gives some interesting history: The "X" designation started as a placeholder in 1890 ("X" as "unknown") and turned out to be a temporarily appropriate moniker:

In the instant before cells divide (high school biology refresher: We're talking about mitosis), the splitting cell's soon-to-be-two-cells pull away from each other while attached at the middle, giving an X appearance. But only 0.01% of your cells are dividing at any given time; the rest of the time things are more blob-like, and the new model will help scientists better understand which of the X chromosome's 153 million base pairs actually sit next to each other in their pasta-like state.

Why this is a big deal: Scientists should be able to better study which of the many bundled-together regions of the chromosome are related to things like aging and disease.

Another discovery reported this week is more galactic — a surprising amount of water on Mars, reported Newser, a USA TODAY content partner providing general news, commentary and coverage from around the Web. Its content is produced independently of USA TODAY.